The overall goal of this application is to continue operation of the National Swine Resource and Research Center (NSRRC). To date, the NSRRC is just beginning its fourth year of operation and it has successfully developed the infrastructure needed to assist swine-based research across multiple disciplines. Functionally the NSRRC has been actively engaged in recruiting and importing swine models into the Center and in distributing cells, tissues, organs and pigs to investigators throughout the United States. The NSRRC also provides invaluable services to the research community by creating new genetically-modified swine models needed by investigators and by training and educating scientists regarding the use of swine in biomedical research. Importantly, we have built an entirely new National Swine Center building, with state-of-the-art high biosecurity, to house all of the functions of the NSRRC. The Specific Aims for the upcoming grant period are as follows: Specific Aims: 1. To operate the National Swine Research and Resource Center. Functions of the NSRRC will continue to include: (a) importation of existing swine models of human health and disease, (b) rederivation of pigs to eliminate pathogens and health monitoring to assure maintenance of a pathogen-free status, (c) cryopreservation and storage of gametes, embryos and somatic cells to prevent future loss of valuable models, (d) distribution of reagents, cells, tissues, organs and designated pathogen-free pigs, and (e) creation of new genetically-modified pigs needed by the biomedical research community. 2. To perform innovative research that will benefit the NSRRC and the biomedical research community. Research projects are aimed at improving: a) the cryopreservation of pig reproductive cells and tissues;b) developing state-of-the-art serologic testing methods for swine health surveillance;and c) the development of improved methods for the production of genetically-modified pigs. The NSRRC will also serve as a site for training and educational activities related to research employing swine models.